4:53 p.m.: A killer quake of magnitude 7.0 strikes 10 miles west of Port-au-Prince, causing untold deaths, collapsing thousands of buildings, severing roads, putting the city's main seaport out of operation, crippling the city. A tsunami warning is issued, later canceled.

By nightfall: fires dot a landscape darkened by the loss of electricity; local hospitals are damaged, overwhelmed; the injured can be heard screaming in the rubble; residents claw at it with bare hands trying to rescue those trapped.

Daybreak: Rescuers claw frantically through rubble; find Port-au-Prince's Catholic Archbishop, Joseph Serge Miot, dead in his office at the cathedral. President René Préval, who escaped collapse of Haitian National Palace, describes stepping over bodies of those killed.

President Barack Obama pledges aid for ``this especially cruel and incomprehensible'' tragedy. He temporarily suspends deporting undocumented Haitians. Thirty-one nations, including China, have aid on its way to Haiti -- including body bags.

A team of doctors from the University of Miami/Jackson Hospital arrives to treat injured, part of U.S.-Haiti Operation Medishare; it flies back a few hours later carrying several Haitian residents gravely injured by the quake.

As darkness falls in Port-au-Prince, shantytowns spring up in every open space, including the manicured lawn of the crumbled Haitian National Palace; homeless erect cloth and cardboard shanties on the soccer field at Stadium Sylvio Cator; people afraid of buildings sleep in cars, on open ground.

President Obama vows Haiti won't be abandoned, promises $100 million in aid.

Later in the day, aid pours in from the world; ships and helicopters from the U.S., search-and-rescue experts from Iceland, doctors and food from France, phone repair help from Ireland, Army engineers from Israel.

Beside the wrecked National Cathedral, volunteers and priests held a makeshift funeral for Archbishop Joseph Serge Miot, killed in the building's collapse.

Offshore, the U.S. Navy's USS Carl Vinson arrived, began helicopter delivery of water to the city's airport, stood ready to airlift in food and other supplies. Nine hundred paratroopers from the 82nd Airborne Division arrived to guard the supplies.

The first wave of Haitian children arrived at Jackson Memorial Hospital's trauma center, with many more expected in the coming weeks.

Mobile The Dominican Institute of Communications says mobile phone service in Haiti was restored after it established a satellite uplink in Port-au-Prince.

The U.N. World Food Program plans to feed 28,000 people in in Port-au-Prince in a single day. The organization is also sending 20.5 metric tons of ready-to-eat meals from El Salvador.

Former presidents Bill Clinton and George W. Bush, begin to oversee fundraising efforts on behalf of Haiti. In an address at the White House, the two men urged the American public to visit their new website: www.clintonbushhaitifund.org to donate and research relief agencies.

U.S. Secretary of State Hillary Rodham Clinton arrives in Port-au-Prince and meets with President René Préval and others on how best to help the recovery effort and Haitian government.

Search-and-rescue teams pull three people from the rubble of the Caribbean Market, including a 7-year-old girl, a 35-year-old man, and a 15-year-old American citizen. International search-and-rescue teams report saving a total of 62 people.

Around noon: Shooting in a Petionville slum forces a convoy carrying enough food for 40,000 people to turn around at noon, as soon as it left the United Nations base near the Port-au-Prince airport. The U.N.'s World Food Program distributes the high-protein biscuits and other goods at Place Boyer, a Petionville park-turned-tent-city.

Prime Minister Jean-Max Bellerive confirmed the death toll so far at 70,000, though that figure included only bodies collected in Port-au-Prince and Leogane. 65,000 are just in the city of Port-au-Prince.

The U.S. State Department confirmed that 16 Americans died in the Haiti quake. An estimated 2,000 Americans have been evacuated.

U.N Secretary General Ban Ki-moon visits the collapsed agency headquarters in Port-au-Prince. Ban says the U.N. is feeding 40,000 people, and expects that figure to rise to 2 million within a month.

Former President and now U.N. Special Envoy to Haiti Bill Clinton visits Port-au-Prince, tours hospitals, disaster areas, declares aid will begin moving faster.

Media and humanitarian group report incidents of looting and gunfire, but U.S. military says there is no widespread disorder.

Vice President Joe Biden says during a prayer breakfast in South Florida that the United States is firmly committed over the long term to helping Haiti recover.

World Food Program announces an agreement with the U.S.-run airport in Port-au-Prince to give humanitarian flights priority in landing.

Dutch adoption agencies and the government sent a chartered plane to Haiti on Monday to airlift out more than 100 children who were in the process of being adopted by parents in the Netherlands before the earthquake.

International Committee of the Red Cross in Geneva reports that people of Port-au-Prince are struggling to survive, as access to shelter, sanitation, water, food and medical care remains extremely limited.

U.S. Defense Secretary Robert Gates says U.S. forces in Haiti can defend themselves and innocent Haitians or foreigners if lawlessness boils over. More than 12,000 U.S. forces are expected to be in the region by end of day.